[lam198]

Hi.
I put new floats and needles in and now it won't hardly rev .
I completely stripped and rebuilt the carbs . It was revving out fine before but leaked fuel. It's now not leaking and fuel is staying where it should. Took carb to local shop and he checked it and float heights are good. At a bit of a loss tbh as I do not want to throw anymore cash at it until it's starting and running as it was. I know everything is pointing at the needles . Running ram air filter pods so not original.

 

[76TWIN]

Need more info before people can help you.
What bike?
Why did you replace the floats and needles? What was wrong with the original ones?

 

[lam198]

Need more info before people can help you.
What bike?
Why did you replace the floats and needles? What was wrong with the original ones?

81 400 SD . With a 450 motor out of a nighthawk.
Original floats and needles caused the fuel to pour out of the carb. That problem is now fixed but it won't rev, it's like a massive flat spot off of tick over.
This was revving great before the change.

 

[76TWIN]

Have you tried it without the pods?
Did you check to make sure you're getting good spark out of both plugs?
Check your ignition timing? Is it advancing properly?

 

[lam198]

Have you tried it without the pods?
Did you check to make sure you're getting good spark out of both plugs?
Check your ignition timing? Is it advancing properly?

Yes with and without filters
Good spark off plugs
I haven't touched the timing. Very few electrics on it to be fair.
Battery>starter solenoid >regulator.

Maybe I need to check the valves. Maybe they're gummed up . When it did start it stunk so maybe that's something to do with it.

 

[Polish]

My valves were way to tight on my 79 CB 400 T and made a difference, for sure check them. Did you do the Ignition Diagnosis? If not here it is.

http://www.hondatwins.net/forums/64...400-450-cb450sc-manual-trans-1978-1986-a.html

 

[J-T]

Just to clarify, was it running good with the pod filters before you changed the float needles or did you change to the pods at the same time?

 

[lam198]

Just to clarify, was it running good with the pod filters before you changed the float needles or did you change to the pods at the same time?

All running with pods before I changed needles and floats.

 

[Polish]

What about going back to the original floats and needles? You can just clean them.Did you get OEM replacements? Some after market needles are too long. Did you read the Rebuilding VB Carbs tread, might give you a clue?

 

[lam198]

What about going back to the original floats and needles? You can just clean them.Did you get OEM replacements? Some after market needles are too long. Did you read the Rebuilding VB Carbs tread, might give you a clue?

All the old bits where shot. Float needles where badly worn, hence petrol pouring out of the overflow, this is now fixed and the float bowls fill up fine. So this says to me that the needles are the correct length, I think I even measured them and they where the same. I will double check them tomorrow if I can find the old ones.

 

[longdistancerider]

It was running better before the repairs due to the excess fuel, now that you've corrected that problem it's running as I'd expect with the pod filters. Here's some reading material on using pod filters http://www.hondatwins.net/forums/63...4-cb400-cv-carbs-pods-how-make-them-work.html

 

[lam198]

Thanks . Read that last night and ordering some 54mm silicone tube. Jetting will be trial and error as it's a 450.

 

[lam198]

Well. Drilled the jets out and now runs much better, even with the ram air pods. So its getting there. May even get this winter project done after 3 years or so.